Who doesn't love a good party?
I think event design is my favorite kind of design. Everyone involved is usually happy and excited and willing to stretch their creative boundaries a bit.
Little departures in design that are colorful, or fun, or serious, or stoic, or scary, depending on the event's beating heart. Sometimes they include giveaways or prizes! Almost always they are multi-part collections, each piece of the whole to be considered with it's unique requirements but always from the perspective of how it relates to the whole.